Improvement in cutter-heads



A. H. SHIPMAN.

Cutter-Heads;

No. 142,048. PatentedAugust19,1873.-

UNITED S ATES PATENT Orrron.

ALBERT H. SHIPMAN, OF ARCADIA, NEW YORK.

IMPROVEMENT IN CUTTER-HEADS.

Specification forming part of Letters Patent No. 142,048, dated August 19, 1873; application filed August 7, 1873.

To all whom it may concern:

Be it known that I, ALBERT H. SHIPMAN, of Arcadia, in the county of Wayne and State of New York, have invented certain new and useful Improvements in Gutter-Heads forPlan- 'ing and other Machines, of which the following is a specification:

Heretofore, in cutter-heads of planing and other machines, the knives or cutters have been constructed in a spiral form, so as to adapt them to the contour or spiral surface of the head, and fastened thereon at various points by means of bolts or screws. In all such cases the spiral form is imparted to the knives or cutters, and made to retain such spirality at all times, its form or contour remainin g unchanged, whether connected or disconnected from the cutter-head; hence, when it is desired to sharpen the edges of said knives, the utmost skill is required to produce an even and uniform edge and a proper and equal bevel, which are the prerequisite to render practical such cutters or knives. To improve upon such cutters or knives is the object of my invention; and it, among other things, consists in the employment of a straight flat cutter or blade, wrought or fashioned from suitable metal and tempered, so that when applied and secured on a regular warped seat or surface of the head or stock its cuttin gedge will be made to assume a spiral form corresponding to the contour of the surface upon which it is applied, proj eetin g equally throughout its length beyond the edge of the spiral channel or groove, whereby a uniform and smooth cutting or planing action is secured.

In the drawings, Figure 1 is a side elevation of a cutter-head with my improved flexible knife, with the cap-plate removed. Fig. 2 is a similar view, with the cap-plate in position. Fig. 3 is a side view of the flat knife prior to being applied to the cutter head. Fig. 4 is a transverse section of Fig. 2.

Like letters of reference indicate correspondin g parts.

The letter A, in the present instance, designates a cutter head, stock, or cylinder designed specially for that class of planing-machines known as surface-planers. This head is provided with warped seats or surfaces B, extending throughout the entire length'of the body of the same, the side edges of which are equidistant from each other, and each seat or surface is separated from the other by a spiral clearance, channel, or groove, 0, through which a the shavings pass in the usual manner. The whole is formed of cast metal, and the warped seats or surfaces B made smooth and even,so that no elevation or protuberance will be present to interfere with the trueness of the knives or cutters when placed and secured thereon. The blade, knife, or cutter D, which forms the essential feature of this invention, is wrought or fashioned out in a straight fiat state from suitable material, and highly tempered, in order to render it effective in operation, and, further, so as to permanently possess and retain an eminent degree of elasticity and flexibility, the object of the former being, that when its edge is made to assume a spiral or analogousform corresponding to the contour of the warped seat or surface of the cutter head or stock, it will, on being released from the pressure producing such, instantly return to and partake of its original and uniform state or condition. This flat blade, knife, or cutter is made of a length equal to that of the warped surface on the cutter-head, but preferably less in width or crosssection, as clearly illustrated in Fig. 1, the object of this latter being for the purpose of inserting or arranging upon the warped surface B a strip of metal, E, equal in thickness to the knife or cutter, so as to continue the surface of the knife or cutter and present a uniform and equal seat for the cap or binding plate. It is thus evident that the edge of the flat knife or cutter can be made to assume a spiral form, when placed upon the seat 13, by the direct application of bolts or screws, and, when released from pressure, revert to its original flat state, in which state it is easily ground or sharpened by those the least skilled, and a uniform and even edge can be produced throughout its length with rapidity and precision-a result which cannot be secured with those cutters which are wrought in and made always to retain a spiral form. To strengthen the knife or cutter, and secure a regular eutting-edge, and to transform it from a straight to spiral form, and clamp or bind it firmly upon its seat, I employ a cap-plate, F, the interior curved surface of which conforms to the surface B of the cutter-head, so that when fastening bolts or screws are passed down through the cap-plate into the cutter-head, the knife or cutter being first interposed between the two, a clamping action or pressure is secured by forcing in the bolts or screws, and the knife or cutter is compelled to change from its original and normal state to a form corresponding to the warped surface of the capplate and the bed of the cutter-head but when the bolts or screws are slightly loosened, and the knife or cutter removed, it will instantly revert to its original flat or plane state, as illustrated in Fig. 3. \Vhen it is desired to adjust the knife or cutter back into its proper position the edge of the cap-plate contiguous to the cutting-edge can be used as a guide, a block of wood being placed against the cutting edge and slightly tapped. Elongated slots to a are formed inthe rear side of the knife or cutter, and these slots are preferably open at said rear ends of the knife, being so constructed that when the fastening bolts or screws 1) b are passed down through said slots into the cutter-head, for transforming the flat knife or cutter into a spiral form and securing it in this shape upon the seat or surface B, it can be thus rigidly'secured in place or be adjusted in respect to the desired depth of cut, or be removed for grinding or sharpening by simply loosening, without removing, the bolts or screws. When the knife is secured upon its seat by screw-bolts, or by the cap-plate, as

hereinbefore mentioned, a constant pressure outwardly will be exerted upon the screw-bolts or cap-plate by the knife or cutter endeavoring to assume its normal flat state, which will prevent any accidental turning or loosening of the fastening bolts or screws.

By constructing the knife or cutter in a fiat plane state, and providing the means described for converting it into a spiral-edged blade, I am enabled to apply it to cutter-heads of any particular form of curve, which could not be accomplished if the cutter was made to assume and retain a spiral-edge form. This flexible spiral knife, in connection with its capplate and cutter head, is specially designed for use in planing-machines, but will be used in other machines when a spiral cutter is found desirable.

Having thus described my invention, what I claim is- A flexible knife or cutter converted from a flexible flat knife by means of a spiral surface on the cutter-head and a corresponding surface on a cap or confining plate,substantially as described, for the object specified.

In testimony that I claim the foregoing I have hereunto set my hand this 7th day of August, 1873.

ALBERT H. SHIPMAN.

Witnesses:

ALBERT H. NoRRIs, WM. J. PEYTON. 

